With temperatures hitting triple digits across the country, backed up by unprecedented storms like the one that hit the East Coast last month — my 91-year-old father in Bethesda lost power and spent a few days in hotels, when he wasn’t volunteering for the Red Cross, helping to set up cooling centers — the question on many people’s minds is whether and to what extent our increasingly extreme weather can be linked to climate change caused by greenhouse gas emissions.
And, in articles appearing on a range of websites, the answers range from cautious — we need more research — to unqualified.
In an article on the Environmental Protection website – not to be confused with the EPA — Steve Vavrus, a senior scientist at the Nelson Institute Center for Climatic Research at the University of Wisconsin-Madison acknowledges the extreme weather but says further study is needed to see if it’s really outside of normal variations.
But he says heat waves like the current one will become more common on a warmer planet as we continue to add greenhouse gases such as carbon dioxide to the atmosphere, primarily through the burning of fossil fuels.
“I think it’s a harbinger of what’s to come under greenhouse warming,” says Vavrus. “Virtually all climate models simulate more intense and frequent heat waves as the climate warms, and most of the world has experienced increases in extreme heat during the past several decades.”
Just how unusual are the current heat spikes and other extreme weather events?
“For the last 40 years of global warming, there is nothing comparable in the instrumental record since about 1880,” said Jack Williams, director of the Nelson Institute Center. “To find comparable analogs for the amount of warming expected for this century under standard greenhouse gas emission scenarios, you have to go back to the climate changes accompanying the last deglaciation, about 20,000 years ago.”
Writing on The Washington Post website, enviro-energy reporter Brad Plumer cites the the National Climatic Data Center’s “State of the Climate” report for June 2012.
The last 12 months in the mainland United States, it notes, were the warmest on record. What’s notable, however, is that every single one of the last 13 months were in the top third for their historical distribution (i.e., April 2012 was in the top third for warmest Aprils, etc).
“The odds of this occurring randomly,” notes NCDC, “is 1 in 1,594,323.”
Plumer also cites a recent article by Associated Press reporter Seth Borenstein, who talked with a dozen climate scientists on what’s going on. The verdict, as summarized in the article’s title, is ”This US summer is ‘what global warming looks like’”
“What we’re seeing really is a window into what global warming really looks like,” said Princeton University geosciences and international affairs professor Michael Oppenheimer. “It looks like heat. It looks like fires. It looks like this kind of environmental disasters.”
The summer heat wave in the Coachella Valley may not have broken any records yet, but it’s still worrisome given concerns about power supplies in the wake of the ongoing closure of the San Onofre nuclear power plant near San Clemente, which I wrote about last month.
Right now we’re staying ahead of the curve, but usage is going up with the heat. Today’s forecast peak demand is 41,930 megawatts, while tomorrow’s is intended to shoot up to 43,797 megawatts. Peak supplies, more than 50,000 megawatts, are still well ahead of demand.
Southern California Edison also has a Outage Center with an interactive map where you can see who’s lost power and the status of repairs. As I type, we have an isolated outage in Rancho Mirage, affecting one person.
But the really big, unanswered question behind all the articles and information, is how much longer are law-makers in Washington, D.C. going to sit around playing politics with a national plan for climate change, reducing greenhouse emissions and promoting renewable energy?
Extreme weather is a signal that the world is approaching a tipping point where even more radical and swift climate change could overtake us. The problem, of course, is that we probably won’t know if we’ve tipped until it’s too late.